In 1937, O’Shaugnessey published in The Lancet that the greater omentum could be used to revascularize areas of schemic damage. The greater omentum gained interest as a reconstructive tool, but its use was limited because it could not reach distant locations. In 1948, the American surgeon Cannaday lengthened the omentum at the vascular pedicle and thus allowed distant sites such as the brain and the lower extremity to be reached.1 This article describes a 64-year-old woman who underwent omental flap breast reconstruction followed by a very late (> 20 years) hernia at the pedicle transposition site.

CASE REPORT

A 64-year-old woman underwent right radical mastectomy 30 years ago. She presented for reconstruction 6 years later. A silicone gel implant was used to reconstruct the pectoralis defect and another implant was used to reconstruct the breast mound. A pedicled omental flap covered both implants. The omentum was then covered with a split-thickness skin graft. On the contralateral side, a subcutaneous mastectomy and reconstruction with a Silastic implant was performed to create a more symmetric result and to satisfy the patient’s desire for bilateral mastectomy.

Twenty-four years later, this patient presented with an incisional hernia under the right costal margin that was particularly uncomfortable when standing for long periods of time. Her medical history is notable for coronary artery disease, hypertension, hypercholesterolemia, mitral valve prolapse, migraines, and diverticulitis.

At operation, the stomach and gastrocolic omentum were present in the hernia. The stomach was freed and returned to the intraperitoneal space, leaving the gastroepiploic pedicle coming through the abdominal wall defect. Despite the long period of time since transfer, there was concern that ligation of the gastroepiploic artery might lead to omental flap necrosis. The pedicle was cross-clamped and the flap was evaluated clinically and by laser Doppler perfusion imaging (Lisca Development AB, Linkoping, Sweden) to assess its perfusion. The skin graft became mottled; however, it was difficult to determine whether it would remain viable if the pedicle were ligated.

When the gastroepiploic pedicle to the omentum was cross-clamped, the perfusion in the flap dropped 27 percent from its preoperative value. At the same time, the contralateral breast’s perfusion had risen 12 percent from its preoperative value. When the pedicle was unclamped, the flap’s perfusion rose by 21.9 percent above its preoperative value and rose 67 percent over its cross-clamped value. This clearly indicated that the original gastroepiploic pedicle to the omental flap was providing a substantial portion of the blood supply to the omental flap, and that transecting the pedicle during the hernia repair might place serious strain on the omentum and overlying skin. As a result, it was decided to perform the herniorrhaphy without transsection of the vascular pedicle. Repair of the incisional hernia was performed after first transposing the pedicle extraanatomically between the eleventh and twelfth ribs. The hernia was repaired by primary repair and SIS reinforcement (Cook Surgical, Bloomington, Ind.). The patient has done well postoperatively and has subsequently experienced relief of her symptoms.

DISCUSSION

The omentum is a useful reconstructive tissue because of its rich vascularity, as pointed out by the German surgeon Paunz in 1926. In addition, it has significant antimicrobial properties. Thanks to the work of Cannaday in 1948, we know that the omentum is versatile because of its ability to be exteriorized on a vascular pedicle anywhere from the brain to the lower extremity.2 Plastic surgeons armed with free-tissue transfer technology have found that the omental and epiploic vessels have external diameters suitable for anastomosis (right gastroepiploic artery, 2 to 3.5 mm; venae comitantes, 2.5 to 3.9 mm; right omental artery, 1.8 to 2.9 mm).

Omental reconstruction is not without its pitfalls, however. The most common of all the complications are hernias in the pedicled omentoplasty. Van Garderen et al. describe incisional hernia in the extraabdominal omentoplasty as “almost inevitable.” They reported that seven of 35 (20 percent) of extraabdominal pedicled omentoplasties resulted in incisional hernias that required operative correction. 3 Contant et al. in 1996 reported nine postoperative hernias out of 34 patients (26 percent) for whom the pedicled omental flap was used to reconstruct chest wall defects.

The patient was a 64-year-old woman who suffered a similar fate, an incisional hernia, some 24 years after her omentoplasty breast reconstruction. In planning her operation, there was concern as to whether it would be necessary to save the original gastroepiploic artery pedicle to the omentum. Van Garderen et al. reported ligating the vascular pedicle and closing the fascial defect in seven of their patients who suffered postoperative herniation.3All flaps did well secondary to presumed neovascularization from surrounding tissues. This patient, however, had an unusual situation in that the omentum is covered by a “parasitic” split-thickness skin graft and lies on an implant. It is unlikely that much vascular in growth had occurred.

The use of laser Doppler flowmetry is well established for measuring the skin microcirculation. 5,6 The laser Doppler technology had previously been limited by the high spatial resolution (< 1 mm) of these devices, as it has been consistently shown that there is substantial spatial variation in tissue perfusion values, even at adjacent sites.7,8 This limitation has been overcome recently by the development of scanning laser Doppler machines that sequentially scan a piece of tissue using a moving laser beam to obtain a picture of perfusion over a broad area of tissue and then present the results as a mean perfusion value.9

One limitation of the laser Doppler perfusion imager is the inability to translate the perfusion values obtained into an absolute number of milliliters per gram per minute.9 Nevertheless, relative comparisons of tissue perfusion can be made using this machine, and to do this we have reported the tissue perfusion by percent change from preoperative baseline values.

Furthermore, because the laser Doppler machine does not physically contact the patient, this design has solved the sterility issues that have plagued other laser Doppler designs in the past. Scanning laser Doppler imagers have been used to analyze axial and random pattern flaps in the maxillofacial area,10 skin blood flow in the hand after microvascular repair of the ulnar artery at the wrist,11 and even perfusion to the gastric tube during esophageal resection.12

The laser Doppler perfusion scan aided us clinically and prevented us from potentially losing the patient’s long-standing flap. It is certainly possible that the flap would have been fine with primary pedicle ligation. The scan dissuaded us from taking that risk. Future studies might include delineation of what percentage resection in perfusion will lead to tissue necrosis.

SUMMARY

We have presented the case of a 64-year-old woman who had undergone a true Halsted radical mastectomy 30 years ago and reconstruction 24 years ago with two silicone gel prostheses, a pedicled omental flap, and skin graft, who recently presented with a ventral hernia. Given her age and medical history, it was unclear as to whether transection of the omental pedicle would be safe. After the laser Doppler imager showed that the perfusion to the omental flap increased 67 percent over the cross-clamped value when the cross-clamp was removed from the omental pedicle, it was determined that this pedicle was providing the majority of blood flow to the omental flap and consequently that transection would not be safe.